From: Hao Wu <hao.wu@rubrik.com>
To: Jarkko Sakkinen <jarkko@kernel.org>
Cc: Shrihari Kalkar <shrihari.kalkar@rubrik.com>,
Seungyeop Han <seungyeop.han@rubrik.com>,
Anish Jhaveri <anish.jhaveri@rubrik.com>,
peterhuewe@gmx.de, jgg@ziepe.ca, linux-integrity@vger.kernel.org,
Paul Menzel <pmenzel@molgen.mpg.de>,
Ken Goldman <kgold@linux.ibm.com>,
zohar@linux.vnet.ibm.com, why2jjj.linux@gmail.com,
Hamza Attak <hamza@hpe.com>,
gregkh@linuxfoundation.org, arnd@arndb.de,
Nayna <nayna@linux.vnet.ibm.com>,
James.Bottomley@hansenpartnership.com
Subject: Re: [PATCH] Fix Atmel TPM crash caused by too frequent queries
Date: Wed, 23 Jun 2021 22:49:27 -0700 [thread overview]
Message-ID: <51DCB704-8E9D-40DD-9E81-F1D16EB28BD5@rubrik.com> (raw)
In-Reply-To: <20210623133518.5vykitqsdwtfqzd6@kernel.org>
> On Jun 23, 2021, at 6:35 AM, Jarkko Sakkinen <jarkko@kernel.org> wrote:
>
> On Sun, Jun 20, 2021 at 04:18:09PM -0700, Hao Wu wrote:
>> This is a fix for the ATMEL TPM crash bug reported in
>> https://patchwork.kernel.org/project/linux-integrity/patch/20200926223150.109645-1-hao.wu@rubrik.com/
>>
>> According to the discussions in the original thread,
>> we don't want to revert the timeout of wait_for_tpm_stat
>> for non-ATMEL chips, which brings back the performance cost.
>> For investigation and analysis of why wait_for_tpm_stat
>> caused the issue, and how the regression was introduced,
>> please read the original thread above.
>>
>> Thus the proposed fix here is to only revert the timeout
>> for ATMEL chips by checking the vendor ID.
>>
>> Test Plan:
>> - Run fixed kernel with ATMEL TPM chips and see crash
>> has been fixed.
>> - Run fixed kernel with non-ATMEL TPM chips, and confirm
>> the timeout has not been changed.
>
> Please move test plan right before diffstat if you wan to include such,
> so that it does not go into the commit log.
Hi Jarkko, not sure I understood your suggestion or not. I removed
the test plan from the commit message in a updated commit
https://patchwork.kernel.org/project/linux-integrity/patch/20210624053321.861-1-hao.wu@rubrik.com/
Let me know if I misunderstood this. I am fine to not include test plan,
If this is not something expected by linux community.
I personally think it is helpful to understand the confidence of the commit.
>
>> ---
>> drivers/char/tpm/tpm.h | 9 ++++++++-
>> drivers/char/tpm/tpm_tis_core.c | 19 +++++++++++++++++--
>> include/linux/tpm.h | 2 ++
>> 3 files changed, 27 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
>> index 283f78211c3a..bc6aa7f9e119 100644
>> --- a/drivers/char/tpm/tpm.h
>> +++ b/drivers/char/tpm/tpm.h
>> @@ -42,7 +42,9 @@ enum tpm_timeout {
>> TPM_TIMEOUT_RANGE_US = 300, /* usecs */
>> TPM_TIMEOUT_POLL = 1, /* msecs */
>> TPM_TIMEOUT_USECS_MIN = 100, /* usecs */
>> - TPM_TIMEOUT_USECS_MAX = 500 /* usecs */
>> + TPM_TIMEOUT_USECS_MAX = 500, /* usecs */
>> + TPM_TIMEOUT_WAIT_STAT = 500, /* usecs */
>> + TPM_ATML_TIMEOUT_WAIT_STAT = 15000 /* usecs */
>> };
>>
>> /* TPM addresses */
>> @@ -189,6 +191,11 @@ static inline void tpm_msleep(unsigned int delay_msec)
>> delay_msec * 1000);
>> };
>>
>> +static inline void tpm_usleep(unsigned int delay_usec)
>> +{
>> + usleep_range(delay_usec - TPM_TIMEOUT_RANGE_US, delay_usec);
>> +};
>> +
>> int tpm_chip_start(struct tpm_chip *chip);
>> void tpm_chip_stop(struct tpm_chip *chip);
>> struct tpm_chip *tpm_find_get_ops(struct tpm_chip *chip);
>> diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
>> index 55b9d3965ae1..9ddd4edfe1c2 100644
>> --- a/drivers/char/tpm/tpm_tis_core.c
>> +++ b/drivers/char/tpm/tpm_tis_core.c
>> @@ -80,8 +80,12 @@ static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask,
>> }
>> } else {
>> do {
>> - usleep_range(TPM_TIMEOUT_USECS_MIN,
>> - TPM_TIMEOUT_USECS_MAX);
>> + if (chip->timeout_wait_stat &&
>> + chip->timeout_wait_stat >= TPM_TIMEOUT_WAIT_STAT) {
>> + tpm_usleep((unsigned int)(chip->timeout_wait_stat));
>> + } else {
>> + tpm_usleep((unsigned int)(TPM_TIMEOUT_WAIT_STAT));
>> + }
>> status = chip->ops->status(chip);
>> if ((status & mask) == mask)
>> return 0;
>> @@ -934,6 +938,8 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
>> chip->timeout_b = msecs_to_jiffies(TIS_TIMEOUT_B_MAX);
>> chip->timeout_c = msecs_to_jiffies(TIS_TIMEOUT_C_MAX);
>> chip->timeout_d = msecs_to_jiffies(TIS_TIMEOUT_D_MAX);
>> + /* init timeout for wait_for_tpm_stat */
>> + chip->timeout_wait_stat = TPM_TIMEOUT_WAIT_STAT;
>> priv->phy_ops = phy_ops;
>> dev_set_drvdata(&chip->dev, priv);
>>
>> @@ -983,6 +989,15 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
>>
>> priv->manufacturer_id = vendor;
>>
>> + switch (priv->manufacturer_id) {
>> + case TPM_VID_ATML:
>> + /* ATMEL chip needs longer timeout to avoid crash */
>> + chip->timeout_wait_stat = TPM_ATML_TIMEOUT_WAIT_STAT;
>> + break;
>> + default:
>> + chip->timeout_wait_stat = TPM_TIMEOUT_WAIT_STAT;
>> + }
>> +
>> rc = tpm_tis_read8(priv, TPM_RID(0), &rid);
>> if (rc < 0)
>> goto out_err;
>> diff --git a/include/linux/tpm.h b/include/linux/tpm.h
>> index aa11fe323c56..35f2a0260d76 100644
>> --- a/include/linux/tpm.h
>> +++ b/include/linux/tpm.h
>> @@ -150,6 +150,7 @@ struct tpm_chip {
>> bool timeout_adjusted;
>> unsigned long duration[TPM_NUM_DURATIONS]; /* jiffies */
>> bool duration_adjusted;
>> + unsigned long timeout_wait_stat; /* usecs */
>>
>> struct dentry *bios_dir[TPM_NUM_EVENT_LOG_FILES];
>>
>> @@ -269,6 +270,7 @@ enum tpm2_cc_attrs {
>> #define TPM_VID_INTEL 0x8086
>> #define TPM_VID_WINBOND 0x1050
>> #define TPM_VID_STM 0x104A
>> +#define TPM_VID_ATML 0x1114
>>
>> enum tpm_chip_flags {
>> TPM_CHIP_FLAG_TPM2 = BIT(1),
>> --
>> 2.29.0.vfs.0.0
>>
>>
>
> /Jarkko
Hao
next prev parent reply other threads:[~2021-06-24 5:49 UTC|newest]
Thread overview: 91+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-20 23:18 [PATCH] Fix Atmel TPM crash caused by too frequent queries Hao Wu
2021-06-23 13:35 ` Jarkko Sakkinen
2021-06-24 5:49 ` Hao Wu [this message]
2021-06-29 20:06 ` Jarkko Sakkinen
2021-06-30 4:27 ` Hao Wu
2021-06-24 5:33 ` Hao Wu
2021-06-29 20:07 ` Jarkko Sakkinen
2021-06-30 4:22 ` [PATCH] tpm: fix ATMEL " Hao Wu
2021-07-02 6:35 ` Jarkko Sakkinen
2021-07-02 7:12 ` Greg KH
2021-07-02 7:33 ` Hao Wu
2021-07-02 7:35 ` Hao Wu
2021-07-02 7:45 ` Jarkko Sakkinen
2021-07-02 7:59 ` Hao Wu
2021-07-02 8:42 ` Jarkko Sakkinen
2021-07-02 11:57 ` Jarkko Sakkinen
2021-07-02 19:16 ` Hao Wu
2021-07-05 5:19 ` Jarkko Sakkinen
2021-07-05 5:29 ` Hao Wu
2021-07-04 0:07 ` Hao Wu
2021-07-05 7:15 ` Jarkko Sakkinen
2021-07-05 23:09 ` Hao Wu
2021-07-06 12:34 ` Mimi Zohar
2021-07-07 4:18 ` Hao Wu
2021-07-07 4:34 ` Hao Wu
2021-07-07 4:31 ` [PATCH v2] " Hao Wu
2021-07-07 9:24 ` Jarkko Sakkinen
2021-07-07 18:28 ` Hao Wu
2021-07-07 21:10 ` Jarkko Sakkinen
2021-07-09 4:43 ` Hao Wu
2021-07-09 4:40 ` [PATCH v2] tpm: fix Atmel " Hao Wu
2021-07-09 17:47 ` Jarkko Sakkinen
2021-07-09 19:23 ` Hao Wu
2021-07-11 7:37 ` Hao Wu
2021-07-16 5:30 ` Hao Wu
2021-07-11 7:51 ` [PATCH v3] " Hao Wu
2021-07-27 2:46 ` Jarkko Sakkinen
2021-07-27 3:40 ` Hao Wu
2021-08-14 22:25 ` [PATCH v4] " Hao Wu
2021-08-26 5:38 ` Hao Wu
2021-08-26 16:24 ` Jarkko Sakkinen
2021-08-27 0:35 ` Hao Wu
2021-09-04 21:14 ` Hao Wu
2021-09-04 23:15 ` Hao Wu
2021-09-05 3:51 ` [PATCH v5] " Hao Wu
2021-09-07 17:43 ` Jarkko Sakkinen
2021-09-08 8:33 ` Hao Wu
-- strict thread matches above, loose matches on Subject: below --
2020-09-26 22:31 [PATCH] Fix " Hao Wu
2020-09-26 22:57 ` James Bottomley
2020-09-26 23:10 ` Hao Wu
2020-09-27 18:25 ` James Bottomley
2020-09-28 0:11 ` Hao Wu
2020-09-28 0:15 ` Hao Wu
2020-09-28 1:22 ` James Bottomley
2020-09-28 5:59 ` Hao Wu
2020-09-28 22:11 ` James Bottomley
2020-09-29 4:46 ` Hao Wu
2020-09-30 2:16 ` Jarkko Sakkinen
2020-09-30 14:54 ` James Bottomley
2020-09-30 15:37 ` Jarkko Sakkinen
2020-09-30 20:48 ` James Bottomley
2020-09-30 21:09 ` Jarkko Sakkinen
2020-09-30 22:31 ` James Bottomley
2020-10-01 1:50 ` Jarkko Sakkinen
2020-10-01 4:53 ` James Bottomley
2020-10-01 18:15 ` Nayna
2020-10-01 18:32 ` James Bottomley
2020-10-01 23:04 ` Jarkko Sakkinen
2020-10-17 6:11 ` Hao Wu
2020-10-18 5:09 ` Jarkko Sakkinen
2020-10-18 5:20 ` Hao Wu
2020-11-14 4:39 ` Hao Wu
2020-11-18 21:11 ` Jarkko Sakkinen
2020-11-18 23:23 ` Hao Wu
2021-05-09 6:18 ` Hao Wu
2021-05-09 6:31 ` Hao Wu
2021-05-10 2:17 ` Mimi Zohar
2021-05-10 3:15 ` Hao Wu
2021-05-10 17:28 ` Jarkko Sakkinen
2020-09-28 1:08 ` Jarkko Sakkinen
2020-09-28 6:03 ` Hao Wu
2020-09-28 14:16 ` Jarkko Sakkinen
2020-09-28 17:49 ` Hao Wu
2020-09-28 19:47 ` Jarkko Sakkinen
2020-09-28 20:27 ` Hao Wu
2020-09-30 2:11 ` Jarkko Sakkinen
2020-09-30 3:41 ` Hao Wu
[not found] ` <EA1EE8F8-F054-4E1B-B830-231398D33CB8@rubrik.com>
2020-10-01 14:16 ` Mimi Zohar
2020-09-14 6:13 Hao Wu
2020-09-14 6:17 ` Greg KH
2020-09-15 2:52 ` Hao Wu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=51DCB704-8E9D-40DD-9E81-F1D16EB28BD5@rubrik.com \
--to=hao.wu@rubrik.com \
--cc=James.Bottomley@hansenpartnership.com \
--cc=anish.jhaveri@rubrik.com \
--cc=arnd@arndb.de \
--cc=gregkh@linuxfoundation.org \
--cc=hamza@hpe.com \
--cc=jarkko@kernel.org \
--cc=jgg@ziepe.ca \
--cc=kgold@linux.ibm.com \
--cc=linux-integrity@vger.kernel.org \
--cc=nayna@linux.vnet.ibm.com \
--cc=peterhuewe@gmx.de \
--cc=pmenzel@molgen.mpg.de \
--cc=seungyeop.han@rubrik.com \
--cc=shrihari.kalkar@rubrik.com \
--cc=why2jjj.linux@gmail.com \
--cc=zohar@linux.vnet.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).